December 1 Release

Chapter 5 exercises were added, and additional sets will come online in January for one-way and two-way chi-square test. Thanks again to Dave Harrington, who has generously allowed us to incorporate his problems.

Chapter 7 was extended and edited. The inference for regression section has been added. In this section, we consider the connection between the unemployment rate and the performance of the President’s party in the House of Representatives during midterm elections from 1898 to 2006. Check out this section to see if we find a meaningful trend!

The third and fourth sets of discussion notes cover probability and distributions. In the probability notes, the basics are emphasized along with conditional probability. A special topic — expectation and SD of linear combinations of random variables — is also included, which is a topic that will later be added to the probability chapter. The fourth set of notes covers the normal, geometric, and binomial models. The LaTeX source and a PDF for all discussion notes are included in the downloads (see the Rights section of OpenIntro for what you can do with these products).

Additionally, Chapter 3 underwent an important change since last month. The Poisson distribution replaced the discrete uniform distribution as Section 3.5.2.